Sunbathing: Strategize Your Sun Exposure

Strategizing your sun exposure

Maui to Malibu, Mazatlan to Martinique, the hierarchy of cool is clear on the beach. Bronze gods flex and preen. Mahogany goddesses prance and pose. All stretch full length in the sun and offer their skin to its health-giving rays, while pasty white dweebs cower in the shade.

A lot of those dweebs are probably dermatologists. To hear them tell it, sunbathing is about as healthy as easing yourself into a nice warm bath of chemical carcinogens, and a sun shower equates to acid rain. Tan now and pay later, they say, because there’s no such thing as a healthy tan.

Melanoma rates continue to rise. Sure, depletion of the Earth’s ozone layer can take some blame, but behavioral change is a more likely culprit, according to San Antonio dermatologist Dr. Mark Naylor. More people are beaching, biking, boating and hiking in ever-scantier clothes, sun-tanning and toasting themselves in tanning beds.

Ultraviolet (UV) “radiation levels from indoor tanning devices far exceed those from sunlight,” says the article, adding that the “highest rates of indoor tanning were found among young women; particularly white women aged 18–25 years. Among white women who reported indoor tanning, more than half (57.7%) reported indoor tanning ≥10 times in the past 12 months. Indoor tanning is particularly dangerous for younger users because indoor tanning before age 35 years increases the risk for melanoma by 75%.”

Smoking a cigarette can make you look cool, and so can having a tan, but in the long run neither one is good for you. Smoking just one cigarette probably won’t cause cancer, and occasional mild sun exposure is not likely to cause skin cancer, say the docs. The potential for problems lies in the cumulative effect of exposure.

“You can take a given amount of ultraviolet light (UV) all at once, like people who get sunburns, or a little every day, like the tanners,” says Dr. James Spencer, Professor of Clinical Dermatology at the Mt. Sinai School of Medicine in New York.

“In fact, it turns out that the tanners get more [of certain types] of skin cancers than the burners.”

Melanoma, specifically, however, loves a burn. While the less-dangerous basal-cell and squamous-cell carcinomas happen most often in people who spend a lot of time outdoors, melanoma tends to show up more on areas of the body not usually exposed to the sun. Icelanders, for example, don’t get a lot of sun but average enough wealth to vacation in bright sunny places, and they have a particularly high incidence of melanoma.

So would tropical vacationers do better if they tanned before they traveled? Hardly. Kick-starting a tan with a burn at the beginning of the summer or a few pre-vacation visits to the tanning salon doesn’t accomplish much. The “protection” of a typical salon tan, says Spencer, gives you a not-great Sun Protection Factor (SPF) of about 4.

What SPF do you need? And what is SPF, anyway? An SPF rating represents the number of times by which you supposedly can increase the duration of your solar exposure before getting fried, but it depends on your skin type.

There are six skin types on the so-called Fitzpatrick scale, from extremely light to extremely dark. If you are an extremely light-skinned, red-headed Irishman, for example, it takes about 10 minutes to burn in midday, midsummer sun. SPF 15 means that it multiplies the time you take to burn by 15, so that would be 150 minutes, or 2 ½ hours.

If you are skin type II, you might expect a burn in 20 minutes from the midday sun, which means SPF 15 multiplies that burn time to 5 hours.

One fallacy of sunblocks is that the SPF on a sunscreen actually represents the protection one gets. SPF numbers are set through exposure at a very high density of sunblock application, says Dr. Naylor.

“Nobody ever applies it that heavy or gets that value,” he adds. “Plus, people don’t apply it uniformly, so they burn in some areas. Plus, it gets sweated off, rubbed off, washed off. Even so-called water-proof sunblock is not water proof, just water resistant. So that red-headed Irishman will probably burn in an hour to an hour and a half.”

Another sunblock fallacy is the idea that one actually gets protection during the time before burning, that one is protected just by preventing redness. UV is still getting through and the damage, which can cause cancer and make you look much older than you are as you age, is still happening. If you are tanning day after day, you are still getting more UV than you would with a one-day burn.

After a certain amount of cumulative UV has reached your skin over the years, it’s easier to get cancer from additional exposure. Once you’ve had one episode of tumor, its’ easier to get another one. Especially for such people, a higher sunscreen is needed, 50 SPF or higher, says Dr. Naylor.

Ten years ago, melanomas were believed most commonly to show up in people between the ages of 40 and 50, but the average age of sun-induced melanomas is coming down, according to Dr. Naylor. “I would now amend that to say between 25 and 50, although they can occur at almost any age, including children and teens.

Dr. Naylor says it typically takes three to five “significant hits” by UV on the genetic structure of a single cell to cause the damage or mutation that leads to cancer.

So using the highest SPF you can get makes sense, because nobody ever gets the full value. Just preventing sunburn is an inadequate approach.

As a person who loves outdoor activities, Dr. Naylor says, he uses SPF 50 sunblock, and also recommends covering up to the extent possible, wearing a hat, wearing clothing that the sun does not easily penetrate.

The original idea of sunblock – which was invented during WWII – was to block the burning rays of UVB. Another kind of ultraviolet light, UVA, doesn’t cause burns but does cause cancer and wrinkles. Many of the older-formula sunblocks and sunscreens let UVA pass right through. A popular sunscreen in the past, for example, was PABA, or para-aminobenzoic acid. And a good one it was for UVB, but it didn’t do much for other UV wavelengths.

So until new ratings or terms make shopping for sunblock and sunscreen foolproof, dermatologists recommend you look for “broad-spectrum” products to handle both UVB and UVA. Check to make sure they contain one of the key ingredients for broad-spectrum protection: zinc oxide, titanium dioxide or avobenzone, which is usually identified on the label as Parsol 1789.

Fortunately, in addition to the ounces of prevention, there are new cures. Medications such as tretinoin may help heal the sun’s not-so-sunny effects, particularly that wrinkled and leathery look so many people take on as they age due to the burning and dehydration wrought by the sun.

Vitamin D is the center of another fallacy that bothers Dr. Naylor, the idea that sun exposure is justified by the need for vitamin D produced by sunlight on the skin. But doctors have pointed out that one doesn’t need much sunshine to get the vitamin D we need. Just 45 minutes per week of sunlight falling on the exposed areas of a clothed person should be enough.

“But you don’t need any of that,” says Dr. Naylor. “Vitamin D used to justify tanning, but in North America it should be a diet issue, not sun exposure. Most diets have enough vitamin D, and there’s a lot of supplementation. You don’t need sunlight. If you’re a big believer in vitamin D, you can take multivitamins that contain vitamin D, or vitamin D supplements. Why expose yourself to a potential carcinogen that will age your skin?”

“That’s just my opinion,” he says, “but I’m a guy who sees a lot of melanoma and a lot of tumors, and that really slants your outlook…because they been playing tennis and golf all their life and haven’t worried about it. I’ll see a librarian who’s 40 and looks like 29, and a tanning bed person who’s 20 and looks like 40.”

But doggone it; we bronzed-god youngsters don’t care about that. I mean, a tan makes us look just so darned sexy, doesn’t it?

“During Humphrey Bogart’s era, having a cigarette hanging out of your mouth was thought to make you look sexy,” says Dr. Naylor. “Now it may make you look stupid, or at least uneducated or weak-minded, since most people now accept that smoking is bad for you in a way that we have not quite reached as far as tanning/sun exposure at present.”

The idea that looking good now matters more than looking bad or having medical problems later may be only natural. Melanin, the skin’s tanning molecule, notes Dr. Naylor, evolved as one way to protect us from the sun long enough to achieve the pre-eminent goal of all biological organisms: reproduction.

By the fifth decade of life, enough cells may be damaged by UV that it may take only one more hit to unleash the beast. By then, of course, we’ve had the necessary time to go forth and multiply.

As long as society has established that tanning is attractive, the biological urge to reproduce may motivate even children who have been tutored on the need for sun protection to reject their lessons when they reach their teens.

“It’s tough to get through to teenagers,” Dr. Naylor says. “They want to look good for the opposite sex, and safety issues take a backseat.”

They’re regular rays of sunshine, these dermatological wreckers of other people’s fun.

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